The overarching objective of this study is to engineer solutions to allow people with severe disabilities who require assistance (human or mechanical) while transferring to be able to transfer in their homes, homes of friends/family, and in the community at large (e.g., hotels, restaurants, shopping malls) in a safe, comfortable, efficient, and convenient manner. The intent of this project is to conduct further research and development of the Robotic Assisted Transfer System (RATS) to determine its feasibility and potential for marketability. The ability of people with many conditions (e.g., SCI, MS, ALS, multiple amputations, stroke, traumatic brain injury) to live in their homes and communities with maximal independence often hinges, at least in part, on their ability to transfer or be transferred by an assistant. In order to help people with severe disabilities (PSD) live at home and participate in life's activities, insurance or other agencies may provide for personal attendant care services and in some cases provide stipends for family members providing these services. Further, independent transfers are a common source of upper extremity injuries and joint degeneration that often leads to the need for assistance with transfers over time. Recent research has also shown that many people who can perform independent transfers need assistance when the height differential is greater than 75 mm or the gap between surfaces is greater than 150 mm. For PSD who need human and or mechanical assistance with transfers there are not a lot of good options. During dependent transfers with a human assistant, there is a high risk of injury (both acute and cumulative) to both the wheelchair user and the assistant, especially over the long-term. Different techniques for human assisted transfers have been found to place the assistant at modest risk for injury, and study findings recommended further development and usage of mechanical devices. Research has shown that clinicians in long-term care facilities felt that their risk for injury was significantly reduced when using mechanical transfer assist devices. Bed to chair and chair to toilet transfers are consistently ranked among the most physically stressful tasks required of PSD and caregivers. There are a number of transfer devices that range from sliding boards to wheeled crane-type lifts (e.g., Hoyer lifts) to ceiling mounted track lifts. Of the mechanical assist devices, all are intended for smooth, flat, level surfaces, and none are robotic systems that greatly reduce the strain on caregivers and PSD. The RATS aims to enhance the independence and quality-of-life of PSD through the development and production of a novel robotic assistive technology that will assist them in leading a more normal life while reducing the chance of injury for both the PSD and the caregiver.